Good conduct time

Good conduct time, good time credit, or time off for good behavior is a sentence reduction given to prisoners who maintain good behavior while imprisoned. Good time can be forfeited if a prisoner is determined to have committed disciplinary infractions and/or crimes while incarcerated.

Under U.S. federal law, prisoners serving more than one year in prison get 54 days a year of good time for every year they serve.[1] Thus, a prisoner who is sentenced to 419 days (365 + 54 days) in prison will serve only about 365 days. Thus, prisoners who demonstrate good behavior serve only about 87.1% of their total sentences.

Some prisoners have argued that prisoners serve only about 85.2% of their sentences, because (365 − 54) ÷ 365 ≈ 85.2%, but the statute empowers the Bureau of Prisons to make the calculation, and the Bureau has determined that the 87.1% rate is to be used. The U.S. Supreme Court has upheld this rate as valid.[2] Good time is calculated after sentencing by the Designation and Sentence Computation Center. Rumors constantly circulate within federal prisons that a Good Time Bill will be passed increasing the amount of good time granted to prisoners, and indeed such bills are sometimes introduced.[3]